Multiple electrical outlet strips are versatile and commonly used electrical components which are practical in a wide variety of environments. Multiple electrical outlet strips typically comprise a plurality of electrical outlet receptacles, each having a plurality of electrical plug receiving openings therein (typically three openings, one for a negative plug prong, another for a positive plug prong, and a third for a ground plug prong). In most conventional multiple electrical outlet strips, such as shown in U.S. Pat. Nos. 4,493,515, 4,113,334 and 4,072,401, each electrical outlet receptacle is distinct from the others, requiring them to be individually assembled in the exterior casing for the multiple electrical outlet strip. There have been proposals for providing a number of receptacles so that they are integral with each other, and then mounting them to projections on the bottom of the casing for the multiple electrical outlet strip, such as in U.S. Pat. No. 4,979,907. However such a construction requires mounting of the components to the bottom portion of the casing, which may be undesirable in some circumstances, and which can limit the materials of which the casing is constructed.
According to the present invention a module for use in a multiple electrical outlet strip, and a multiple outlet strip itself, are provided which are extremely easy to assemble in a quick and inexpensive manner, with the module positively held in place within the multiple electrical outlet strip. The component parts are also easy to mold and construct, and may be made of a wide variety of materials; for example, the casing may be made of metal or electrical insulating material, whichever is desired.
According to one aspect of the present invention, a module for use in a multiple electrical outlet strip is provided. The module comprises the following components: A first integral molded component of electrically insulating material having a top face defining a plurality of series of electrical plug receiving openings disposed in line in a first direction. A second integral molded component of electrically insulating material having a bottom face, and a top face opposite the bottom face, and having a length, in the first direction, approximately as long as the first molded component. A plurality of bus bars of electrically conducting material disposed between the first and second molded components, cooperating with the electrical plug receiving openings, each bus bar having an end termination accessible from the exterior of one end of the molded components in the first direction. And, means for securing the first and second molded components together, holding the bus bars in a fixed position with respect to the plug receiving openings.
The module also preferably comprises integral positioning projections formed on the first molded component for positively positioning the bus bars in fixed position with respect to the plug receiving openings. Each of the plurality of series of electrical plug receiving openings preferably comprises three openings, one each for positive, negative, and ground electrical plug prongs. The plurality of bus bars thus comprises three bus bars, negative, positive, and ground bus bars. A plurality of integral hollow projections may be formed on a second molded component and extending upwardly from the top face thereof, and the ground bus bar may have means defining a plurality of openings in it for receipt of the hollow projections (which may be parallelepipeds), the projections stabilizing the position of the ground bus bar. Each bus bar also has portions thereof that preferably extend outwardly from one end of the first and second molded components, and have surface manifestations (e.g. holes) associated with them for receipt of wires from an electrical cord.
The securing means for holding the first and second molded components together may comprise a plurality of threaded fasteners (screws) extending through the bottom face of the second molded component and engaging the first molded component. The first and second molded components may be injection molded of plastic, and the bus bars may be brass, copper, or aluminum. A plurality of screw receiving openings may be formed on the face of the first molded component for connecting the module to an upper surface of a casing for a multiple electrical outlet strip.
The invention also relates to a multiple electrical outlet strip comprising a casing including a casing top portion, and a casing bottom portion. The casing top portion has an upper surface with means defining a plurality of in line openings, each receiving an electrical outlet receptacle, in turn for receipt of an electrical plug. The electrical outlet receptacles may comprise a module as described above, and connecting means are provided for connecting the module to the upper surface of the casing, the connecting means typically comprising screws extending into screw threaded openings in the module upper surface. The casing top and bottom portions, which both may be made of metal, completely contain the module within them, with the electrical outlet receptacles extending outwardly from the casing top portion upper surface.
The invention also comprises a multiple electrical outlet strip comprising: A casing including a casing top portion, and a casing bottom portion, the casing top potion having an upper surface with means defining a plurality of openings, each for receipt of an electrical outlet receptacle, for receipt of an electrical plug therein. A module of electrically insulating material comprising a plurality of integrally formed and connected electrical outlet receptacles, each receptacle having means defining a plurality of electrical plug prong receiving openings therein. A plurality of bus bars of electrically conductive material associated with the module plug prong receiving openings, one bus bar for each prong receiving opening of an electrical receptacle. And, connecting means for connecting the module to the upper surface of the casing, the casing top and bottom portions completely containing the module therewithin, with the electrical outlet receptacles extending outwardly from the upper surface. The casing lower portion may be flat, free of projections, which allows it to be made of metal. The connecting means may comprise a plurality of externally threaded fasteners (screws) and means defining a plurality of through-extending openings in the case top portion upper surface, and means defining a plurality of aligned internally screw threaded openings in the module for receipt of the screw.
It is the primary object of the present invention to provide an inexpensive and easy to assemble multiple electrical outlet strip in which the components are positively held in place, and which has a casing that may be made entirely of metal if desired. This and other objects of the invention will become clear from an inspection of the detailed description of the invention, and from the appended claims.